DOCSLIB.ORG

A08E Western Laptev Sea Region Framework- Structural Style and Timing of Deformation V.E

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
A08E Western Laptev Sea Region Framework- Structural Style and Timing of Deformation V.E A08E Western Laptev Sea Region Framework- Structural Style and Timing of Deformation V.E. Verzhbitsky* (TGS-Nopec Geophysical Company Moscow) & A.K. Khudoley (Saint Petersburg State University) SUMMARY The Laptev Sea region is one of the remote and geologically complex areas of Russian Eastern Arctic. According to the existing seismic data, a number of large offshore sedimentary basins with significant proposed hydrocarbon potential, were revealed on its shelf. No offshore wells were drilled there so far, thus all the information on the regional geology, is based on the very limited amount of marine seismic profiles and our knowledge on adjoining near-coastal areas. This study is based on the series of field works 2008-2009, carried out as a part of TGS-NOPEC Geophysical Company / St Petersburg State University joint project on Geology and Hydrocarbon systems of Northern Siberia. The field observations were done in the Laptev Sea framework, including Taimyr, Verkhoyansk and Olenek fold belts, Siberian craton, Enisey-Khatanga and Anabar-Lena depressions. Here we present some results of structural investigations of the Paleozoic-Mesozoic sedimentary complexes, exposed on Southeastern Taimyr, Bolshoy Begichev Island and Paksa Peninsula/Anabar River mouth. It is shown, that the final stage of compressional deformation in the Western Laptev Sea Region corresponds to Late Kimmerian and so is roughly synchronous with those on the rest of Eastern Arctic area, including New Siberian Islands, Chukotka and Brooks Range. Saint Petersburg 2010 — Saint Petersburg, Russia, 5-8 April 2010 Introduction The Laptev Sea region is one of the remote and geologically complex areas of Russian Eastern Arctic. According to the existing seismic data, a number of large offshore sedimentary basins with significant proposed hydrocarbon potential, were revealed on its shelf. No offshore wells were drilled there so far, thus all the information on the regional geology, is based on the very limited amount of marine seismic profiles and our knowledge on adjoining near-coastal areas. This study is based on the series of field works 2008-2009, carried out as a part of TGS-NOPEC Geophysical Company / St Petersburg State University joint project on Geology and Hydrocarbon systems of Northern Siberia. The field observations were done in the Laptev Sea framework, including Taimyr, Verkhoyansk and Olenek fold belts, Siberian craton, Enisey-Khatanga and Anabar-Lena depressions. Here we present some results of structural investigations of the Paleozoic-Mesozoic sedimentary complexes, exposed on Southeastern Taimyr, Bolshoy Begichev Island and Paksa Peninsula/Anabar River mouth (Figure 1). Figure 1 The fragment of Geological Map, scale 1:2500000 (Petrov, 2004), for Southwestern Laptev Sea region, showing the location of the main areas, studied during 2008-2009 field seasons. The blue rectangle outlines the area, described in this paper. Method In this paper we focus on the problems of structural geology of the region studied. During the field works we have collected significant amount of structural-geological data, including observations and mass-measurements of bedding planes, elements of folds, faults and shear fractures, extensional veins, etc. The data obtained allowed us to restore the main stages of structural/tectonic evolution of the Western Laptev Sea region. Structural style According to the previous results of marine seismic data, directly to the East of Southeastern Taimyr, the existence of ~ south-vergent frontal thrust fault and fold zone, separating deformed complexes of Saint Petersburg 2010 — Saint Petersburg, Russia, 5-8 April 2010 Taimyr fold belt from almost undeformed Paleozoic(?)-Mesozoic sediments of offshore part of Enisey-Khatanga basin (Drachev et al., 2002). Field observations revealed no obvious frontal thrust and fold zone, but we found, that the intensity of the compressional deformation gradually decreases southward from older (Permian, Triassic) to younger (Jurassic-Cretaceous) sequences, towards the offshore part of Enisey-Khatanga basin (Figure 2). Permian strata are deformed in tight to isoclinal folds, complicated by thrusts, often with flat and ramp geometry. Triassic sediments are characterised by open to tight folding with minor thrust faulting. On Paksa Peninsula/Anabar River mouth and Bolshoy Begichev Island the Triassic-Jurassic-Neocomian clastic sequences are involved only in very gentle open folding, complicated by low-amplitude minor opposite-vergent reverse and thrust faults. Based on the measurements of latest extensional mesostructures (small-scale normal faults, extensional fractures) we propose, that the area studied was also subjected by ~ N-S (1) and subsequent E-W (2) extension (Khudoley et al., 2009). J P T K Figure 2 Structural style of the Tsvetkova Cape area (Southeastern Taimyr). Timing of the deformation It is commonly believed, that formation of the Taimyr orogen, representing south-vergent thrust and fold belt, was caused by collision between Siberian craton and Kara microplate. The earliest syncollisional granitoides in the Northern Taimyr zone are dated as 306-275 Ma, corresponding to Late Carboniferous-Early Permian (Vernikovsky, 2009). In the Late Permian time (264-258 Ma) postcollisional granites and granodiorites were intruded into the deformed Precambrian and Paleozoic sequences of Northern- and Central Taimyr zones (Vernikovsky, 2009). Thus, the deformation occurred corresponds to Late Hercynian (Variscian) orogeny. Although Taimyr thrust and fold belt was in general formed to the end of Early Triassic, the deformation (inversion) was continuing during the whole Triassic period (Vernikovsky, 2009). On the basis on our field observations were concluded earlier, that base-Jurassic unconformity is really exist here, but the basal conglomerates has local source and the could correspond not to compressional, but to extensional event (Khudoley et al., 2009). The discovery of a locally distributed thick Upper Jurassic conglomerate unit in the Tsvetkova Cape area of Southeastern Taimyr (Figure 3a) points to significant uplift and erosion in the Taimyr orogen, located directly to the North from the point of observations. We interpret it as an evidence for the earliest stages of the Late Kimmerian orogeny (Khudoley et al., 2009). South-dipping cross- bedding within conglomerate/sandstone beds strongly supports this idea. We also observed, that Jurassic and Neocomian sequences are also involved in the compressional deformation, but Aptian(?)- Albian sediments are close to subhorizontal and likely post-date the compressional deformation Saint Petersburg 2010 — Saint Petersburg, Russia, 5-8 April 2010 (Figure 3b). It is interesting to note, that Messoyakh compressional-transpressional zone, complicating the internal structure of Enisey-Khatanga basin, was active during Late Jurassic- Neocomian time (Kontorovich et al., 1994; Kontorovich, Kalinina, 2009). Figure 3 Evidence of the Late Jurassic-Neocomian regional latest compressional deformation: A - thick Upper Jurassic conglomerate unit in the Tsvetkova Cape area of Southeastern Taimyr; B – Albian subhorizontal coal-bearing strata with cross-bedding on Bolshoy Begichev Island. Thus, it is really important, that the final stage of compressional deformation in the Western Laptev Sea Region corresponds to Late Kimmerian and so is roughly synchronous with those on the rest of Eastern Arctic area, including New Siberian Islands, Chukotka and Brooks Range (Alaska), where it took place in the Late Jurassic-Neocomian, pre-Aptian-Albian time (Kos’ko et al., 1985; Parfenov, 1984; Parfenov, Kuzmin, 2001; Sokolov et al., 2002; Kos’ko, Trufanov, 2002; Kuzmichev et al., 2006; Katkov et al., 2007; Zonenshain et al., 1990; Miller et al., 2002; Miller, Verzhbitsky, 2009). This result is necessary to take into consideration for compilation of any regional plate-tectonic reconstructions. The later extensional stage could take place as early as in Aptian time, but it is likely, that it was most active during rifting/spreading processes in Eurasia Basin/Gakkel Ridge in the latest Late Cretaceous-Cenozoic time (e.g., Drachev et al., 1998; Gaina et al., 2002). Acknowledgements The authors are grateful to their friends and colleagues Ivan Kalmykov, Marianna Tuchkova, Andrey Prokopiev, Alexander Egorov, Mikhail Rogov, Peter Fedorov, Galina Serkina, Dmitry Zdobin, Dmitry Zastrozhnov, Alexey Li and many others for numerous discussions and help and support in organizing and carrying out of the field works. References Drachev S.S., Savostin L.A., Groshev V.G., Bruni I.E. [1998] Structure and geology of the continental shelf of the Laptev Sea, Eastern Russian Arctic // Tectonophysics, 298, 357–393. Drachev S.S. [2002] On the basement tectonics of the Laptev Sea shelf // Geotectonics, 36 (6), 483- 497. Gaina C., Roest W.R., Muller R.D. [2002] Late Cretaceous-Cenozoic deformation of northeast Asia // Earth Planet Sci Letters. 197, 273-286. Katkov S.M., Strickland A., Miller E.L., Toro J. [2007] Ages of granite batholiths from Anyui- Chukotka Foldbelt // Transactions (Doklady) of the Russian Academy of Sciences/Earth Science Section. 414 (4), 515-518. Khudoley A., Verzhbitsky V., Prokopiev A., Frantzen E., Tuchkova M., Egorov A., Serkina G., Vasiliev D., Rogov M., Zastrozhnov D., Li A. [2009] The Northern Siberia Geology and Hydrocarbon Systems: Project and the First Results // 71st EAGE Conference and Exhibition Saint Petersburg 2010 — Saint Petersburg, Russia, 5-8 April 2010 “Balancing
Load more

Recommended publications
  • Chronology of the Key Historical Events on the Eastern Seas of the Russian Arctic (The Laptev Sea, the East Siberian Sea, the Chukchi Sea)
    Chronology of the Key Historical Events on the Eastern Seas of the Russian Arctic (the Laptev Sea, the East Siberian Sea, the Chukchi Sea) Seventeenth century 1629 At the Yenisei Voivodes’ House “The Inventory of the Lena, the Great River” was compiled and it reads that “the Lena River flows into the sea with its mouth.” 1633 The armed forces of Yenisei Cossacks, headed by Postnik, Ivanov, Gubar, and M. Stadukhin, arrived at the lower reaches of the Lena River. The Tobolsk Cossack, Ivan Rebrov, was the first to reach the mouth of Lena, departing from Yakutsk. He discovered the Olenekskiy Zaliv. 1638 The first Russian march toward the Pacific Ocean from the upper reaches of the Aldan River with the departure from the Butalskiy stockade fort was headed by Ivan Yuriev Moskvitin, a Cossack from Tomsk. Ivan Rebrov discovered the Yana Bay. He Departed from the Yana River, reached the Indigirka River by sea, and built two stockade forts there. 1641 The Cossack foreman, Mikhail Stadukhin, was sent to the Kolyma River. 1642 The Krasnoyarsk Cossack, Ivan Erastov, went down the Indigirka River up to its mouth and by sea reached the mouth of the Alazeya River, being the first one at this river and the first one to deliver the information about the Chukchi. 1643 Cossacks F. Chukichev, T. Alekseev, I. Erastov, and others accomplished the sea crossing from the mouth of the Alazeya River to the Lena. M. Stadukhin and D. Yarila (Zyryan) arrived at the Kolyma River and founded the Nizhnekolymskiy stockade fort on its bank.
    [Show full text]
  • An Overview of the Lena River Delta Setting
    Journal of Coastal Research 1083-1093 West Palm Beach, Florida Fall 2000 An Overview of the Lena River Delta Setting: Geology, Tectonics, Geomorphology, and Hydrology Feliks Aret and Erk Reimnitz] t Petersburg State University :j: GEOMAR of Mea ns of Wischhofstra l3 e 1-3 Communications Geb.4 Moskovsky avo9 D-24148 Kiel, Germany St .-Petersburg, 190031 Russia ABSTRACT _ ARE, F. and Reimnitz, E., 2000. An overview of the Lena River Delta setting: geology, tectonics , geomorphology, and .tltllllll:. hydrology. Journal ofCoastal Research, 16(4), 1083-1093. West Palm Beach (Florida), ISSN 0749-0208. • • ~- ~ ~. The Lena River Delta , largest in the Arctic, occupies 32,000 km-. It has a complicated structure caused by neotectonic i!!EJ:il--- block-movements, which formed an island archipelago with elevatio n differences as large as 60 m of distinct geological --=_2_ unit s. The modern active delta occupies spaces between older islands of the archipelago, and is just beginning to -+ S-- protrude into the open sea. The hydrologic pattern in the delta also shows the influence of tectonism . Numerous earthquakes during last century with magnitudes as large as 6 suggest that tectonic movement is contin uing. Radio­ carbon dati ng shows that the modern delta has been built during the second half of the Holocene. The total advance of the delta during this time was 120-150 km. The Lena River is considered the main sediment source for the Laptev Sea. The latest investigations give the suspended sediment load in the lower Lena River at 21 Mt/y, but only < 30% of this load is thought to reach the sea .
    [Show full text]
  • New Records of Spiders (Aranei) from the Russian Arctic Новые Находки Пауков (Aranei) В Российской
    Arthropoda Selecta 26(1): 77–82 © ARTHROPODA SELECTA, 2017 New records of spiders (Aranei) from the Russian Arctic Íîâûå íàõîäêè ïàóêîâ (Aranei) â Ðîññèéñêîé Àðêòèêå A.V. Tanasevitch À.Â. Òàíàñåâè÷ A.N. Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Leninsky prospekt, 33, Moscow 119071, Russia. E-mail: [email protected] Институт проблем экологии и эволюции РАН им. А.Н. Северцова, Ленинский проспект 33, Москва 119071, Россия. KEY WORDS: Russia, spiders, new records, tundra, chorology. КЛЮЧЕВЫЕ СЛОВА: Россия, пауки, новые находки, тундра, хорология. ABSTRACT. New records of 34 spider species & Nadezhda M. Poryadina (1985), Sonya B. Rozen- from the Russian Arctic are presented and supplied feld and Dmitry Nizovtsev (2016). All material is stored with detailed descriptions of their habitats. Some misi- in the Zoological Museum of the Moscow State Uni- dentifications are corrected, the known patterns of dis- versity, Moscow, Russia. tribution of many species are complemented and newly All spiders were collected from the different sub- typified. zones of the tundra belt of Russia’s Eurasia. According to the subzonal differentiation of the tundra zone РЕЗЮМЕ. Приведены новые находки 34 видов [Matveeva, 1998], the localities (see Map) are allocat- пауков в Российской Арктике, сопровождённые ed as follows: the southern tundra subzone, No. 2; the подробным описанием местообитаний. Исправле- typical tundra subzone, Nos 1, 3, 4, 13, 15, 16, 19–21, ны ошибочные определения, известные ареалы мно- and the arctic tundra subzone, Nos 5, 7, 8, 11, 12, 14, гих видов существенно расширены и заново типи- 17, 18. Localities 6, 9 & 10 lie at the border between зированы.
    [Show full text]
  • Structure of the Russian Eastern Arctic Shelf
    STRUCTURE OF THE RUSSIAN EASTERN ARCTIC SHELF V.A. Vinogradov, E.A. Gusev, and B.G. Lopatin, All-Russia Geological Institute for Geology and Mineral Resources of World Ocean (VNIIO), St. Petersburg, Russia, e-mail: [email protected] ABSTRACT sheets. A set of maps consists of tectonic, deep- This study of the Laptevs, East Siberian, and structural, bedrock, Quaternary and bottom sediment, Chukchi sea shelves concentrates mainly on the and geomorphologic maps. Onshore portions of the specific structure of the sedimentary cover and briefly digitized database come from geological mapping of discusses age and structure of the basement. An the eastern Arctic mainland and islands by the Russian elaboration of the tectonic model for the entire Russian Geological Survey in the middle of the last century. eastern Arctic shelf is accompanied by discussions of Geological investigations of the offshore area are rather the existing views on problems which have been poor. They include bottom sampling, piston cores and hampered by absence of deep offshore wells. The most rare shallow seismic profiles. Although several shallow relevant information was obtained from deep seismic boreholes were collected around the New Siberian profiling, which provides data on thicknesses and Islands and exploration wells were drilled on the U.S. unconformities within the sedimentary cover, tectonic Alaska Shelf, the major source of offshore information structures, and structure of the basement surface. But used in this study is from various geophysical methods without well control the age and nature of the basement of investigations by the Marine Arctic Geological and sedimentary cover remain thus far, speculative and Enterprise (MAGE) of Murmansk (Sekretov, 1998; will have to be verified by future research activities.
    [Show full text]
  • The Barents Sea, the White Sea, the Kara Sea)
    Chronology of the Key Historical Events on the Western Seas of the Russian Arctic (the Barents Sea, the White Sea, the Kara Sea) Ninth century 870–890 The travel of Otar, a Viking from the Norwegian province of Hologaland (now Helgeland), who discovered the way to the White Sea. The story of this journey was recorded from his own words by the English King, Alfred the Great. 9th–10th century The beginning of the Russian advance to the north and northeast and their appearance on the shores of the White Sea and the Barents Sea. Tenth century 920 The Viking Eirik Bloodaxe sailed in the mouth of the Northern Dvina (it was called “Vina” in the sagas). 965 The son of Eirik Bloodaxe, the Viking Harald Grey Cloak made a trip to the mouth of the Northern Dvina. Eleventh century 11th century The people of Novgorod, coming out of the White Sea, won Biarmia, the country located on the Pechora River and the Northern Dvina. 1026 The mouth of the Northern Dvina was visited by the Viking Torer Dog, who first engaged in peaceful trade but ended up plundering the temple of Iomala (supposedly located on the site of the current Kholmogory). Twelfth century 12th century (first The mention in the annals of the Terskiy Shore (the White Sea Throat), among Novgorod’s half) possessions. 1110 or 1130 The archbishop of Novgorod, John, founded a monastery of the Archangel Michael (at the mouth of the Northern Dvina), at which there was a settlement, an early precursor of the port and the city of Arkhangelsk.
    [Show full text]
  • Notes on the Fishes of the Severnaya Zemlya Archipelago and the Spawning Area of Polar Cod Boreogadus Saida (Gadidae)
    N.V. Chernova et al. Fishes of the Severnaya Zemlya archipelago Proceedings of the Zoological Institute RAS Vol. 325, No. 2, 2021, pp. 248–268 10.31610/trudyzin/2021.325.2.248 УДК 597.56 Notes on the fishes of the Severnaya Zemlya archipelago and the spawning area of polar cod Boreogadus saida (Gadidae) N.V. Chernova1*, V.A. Spiridonov 2, V.L. Syomin2 and M.V. Gavrilo3 1 Zoological Institute of the Russian Academy of Sciences, Universitetskaya Emb. 1, 199034 Saint Petersburg, Russia; e-mail: [email protected] 2 Shirshov Institute of Oceanology of the Russian Academy of Sciences, Nakhimovsky Prospekt 36, 117997 Moscow, Russia; e-mail: [email protected] 3 Association Maritime Heritage: Explore and Sustain, Icebreaker Krassin, Leitenant Schmidt Emb. 23 line, 199106 Saint Petersburg, Russia; e-mail: [email protected] Submitted May 7, 2021; revised June 5, 2021; accepted June 8, 2021. ABSTRACT Data on the fishes of the high-latitude Severnaya Zemlya archipelago (the North Land) is presented. The archipe- lago is located in the Arctic on the border between the Kara Sea and the Laptev Sea. The ichthyofauna of the ar- chipelago has not been studied; therefore, even small collections are of interest. Fish samples were obtained during the expedition “Open Ocean: Arctic Archipelagos – 2019: Severnaya Zemlya”. In addition, the samples from this area in the collections of the Zoological Institute (ZIN) were studied, which have been received from polar ex- peditions to the Kara and Laptev seas during the entire era of polar research. The most significant fact is the dis- covery of mass accumulation of polar cod Boreogadus saida (Lepechin, 1774) larvae in Mikoyan Bay (Bolshevik Island), which gives evidence of important spawning grounds near Severnaya Zemlya.
    [Show full text]